{
  "pools": {
    "A": { "servers": [ "localhost:12345" ] },
    "B": { "servers": [ "localhost:12346" ] },
    "C": { "servers": [ "localhost:12347" ] }
  },
  "route": {
    "type": "PrefixSelectorRoute",
    "policies": {
      "a": {
        "type": "PoolRoute",
        "pool": "A",
        "shard_splits": { "1": 3 },
        "shadows": [
          {
            "target": "PoolRoute|C",
            "index_range": [0, 1],
            "key_fraction_range": [0, 1],
            "shard_splits": {}
          }
        ]
      },
      "b": {
        "type": "FailoverWithExptimeRoute",
        "normal": {
          "type": "PoolRoute",
          "pool": "B",
          "shard_splits": { "2": 10 }
        },
        "failover": "PoolRoute|A"
      }
    }
  }
}
